Automatic web threading arrangement



Ap 1965 P. R. TROUT, JR, ETAL 3,173,124

AUTOMATIC WEB THREADING ARRANGEMENT Filed March 22, 1965 2 Sheets-Sheet 1 PgrryR. 'lrout ,Jr. E znarw Jensen/ INVENTORS BY @WM use Mae m ww .ATTORNEJ'S P. R. TROUT, JR.. ETAL 3,178,124

AUTOMATIC WEB THREADING ARRANGEMENT April 13, 1965 2 Sheets-Sheet 2 Filed March 22, 1963 .llEer INTI-out Jr.

2 nsen "U inaI-WVJ Je TORI-VHS 3,178,124 AUTOMATIC WEB THREADING ARRANGEMENT Perry R. Trout, Jr., and Einar W. Jensen, Rochester, N.Y., assignors to Eastman Kodak Company, Rochester, N.Y., a corporation of New Jersey Filed Mar. 22, 1963, Ser. No. 267,277 9 Claims. (Cl. 242-56) This invention relates to an automatic web threading arrangement and, more particularly, to an automatic web threading apparatus operable at high speeds.

Many web threaders are known today and are used in Various apparatus such as complex printing presses, photographic finishing equipment and the like. However, usually these web threaders operate at a low speed and often at such a low speed that certain of the more intricate operations of threading may be accomplished by hand. In processing equipment, wherein the web itself is changed in form or chemical composition during its traversal of a machine, the lead portion of the web is invariably destroyed if the threading operation is substantially slower than the normal operating speed of the equipment. One solution to this problem is to provide an inert sacrifice leader portion. However, this effectively increases the size of the web handling equipment necessary and causes additional set-up and shutdown operations which often work out to be as expensive as wasting a portion of the web being processed. In automatic processing equipment for photographic films wherein hundreds or thousands of images are placed on a strip of photographic paper web, many feet are required to complete the threading of the web through a series of developer, washer, fixer, washer, dryer, etc., equipments. This threading is even more difiicult because of the requirement that processing be accomplished in darkened quarters. Since economy dictates that the developing process be relatively rapid, it is becoming increasingly difiicult to accomplish threading of such a web at a speed allowing any hand operations during the threading operation without using sacrifice lead portions or substantial waste of webbing.

Therefore, an object of the present invention is to provide a high-speed automatic threading arrangement which will both traverse a tortuous path and detach itself from the web upon completion of the threading operation.

Another object of the present invention is to provide a simple and reliable arrangement for detaching a rapidly moving towbar from a web drawn thereby.

In accordance with one embodiment of our invention, a chain-driven towbar is arranged to traverse a complete and complex processing path of a web. The web to be processed is supplied either from exposing equipment or in the form of a reel wherein thousands of photographic images have been imprinted thereon. The web is initially coupled to the towbar. The processing machine drive and the towbar drive are then started, the towbar draws the web through all of the processing equipments and to a take-up spool core so that the web is secured thereto, and the towbar eliects its being disconnected from the web to return to its stand-by position. The towbar itself actuates means for coupling the web to the take-up spool core and means for severing the web between the core and the towbar. Using such an arrangement, it is feasible to thread the equipment at speeds up to 290 feet per minute so that none of the leader material which is in various portions of the processing machine need be destroyed because of stoppage necessary to accomplish hand operations or low-speed operations.

The subject matterwhich is regarded as our invention is particularly pointed out and distinctly claimed in the concluding portion of this specification. The invention,

' United States Patent 3,178,124 Patented Apr. 13, 1965 however, as to its organization and operation together with further objects and advantages thereof, will best be understood by reference to the following description taken in connection with the accompanying drawings in which:

FIG. 1 is a diagrammatic plan view of a processing equipment wherein the present invention is useful;

FIG. 2 is a diagrammatic view of the equipment illustrated in FIG. 1 wherein details necessary for securing the web to the take-up spool core and disconnecting the web from the towbar are shown;

FIG. 3 illustrates the web securing operation;

FIG. 4 illustrates the towbar release operation; and

FIG. 5 is an enlarged perspective view of the spool core shown in FIGS. 2, 3, and 4.

Referring now to the drawings wherein like numbers refer to similar parts, we have shown in FIG. 1 a web 10 being drawn from a reel 11 through a plurality of processing tanks such as a developer 12, a fixer 13, a washer 14 and a dryer 15. The web 10 then proceeds to a take-up reel 16 driven by a motor 17. Transporting of the web it is accomplished by a plurality of transport mechanisms shown as rollers 18.

There is also drivable by a motor 19 throughout the path of the web 10 over the rollers 18 a towbar 20 on a chain-drive 22. Both of the motors 17 and 19 are energizable from power terminals 21. The chain-drive 22 and the motor 15 are towbar drive means which transport the towbar 20 over the web transport rollers 18 on the same side thereof as is traversed by the web 10 until it reaches the take-up spool core 24. The core 24 has previously been provided with a means for grasping and securing the web thereto such as an activated glue 23 as illustrated in FIG. 5. The glue 23 will secure the dry web it) being transported therearound from the region of the dryer 15. The towbar 26 on the chain-drive 22 is then transported by sprocket wheels 25 to the stand-by position illustrated in FIG. 1, whereupon a next web 10 may be secured thereto when a next reel 16 is to be started through the processing equipment 12-15. Although not specifically shown in the drawing of FIG. 1, sprockets are provided in proximity with the ends of each of the web transport rollers 18 so that the towbar 2t) and its chain-drive 22 may be driven therearound. Such sprocket drives along the path of a web traversal are well known and need not be described in detail here.

Also, several of the web transport rollers 18 may be driven by the motor 17 or by synchronized motors (not shown), and additional sprocket wheels may be driven by the motor 19. It is common practice to have a web drive motor start switch 26 interlocked by a feeler 27 to an output portion of the web 10 so that the reel 16 will stop when the complete web is wound thereon or when the web tension is lost. In accordance with our invention, since the spool core 24 must be running at full speed when the web 10 is secured thereto, a second interlock link 23 is provided to maintain operation of the motor 17 during energization of the towbar motor 19. Thus, the switch 26 is coupled by the interlock link 28 to a towbar motor start and run switch 29. We prefer that the interlock link 28 also operate to close the switch 26 when the switch 29 is initially closed. As is discussed in greater detail below, the towbar motor switch 29 is automatically opened as the towbar 20 returns to stand-by as shown in FIG. 1.

Referring now to FIG. 2, the more complex portion of the threading operation is shown in the form of a slapper 30 drivable to engage the web 10 and force it tightly against the take-up spool core 24. The sprocket wheel 25 in the region of the core 24 is shown as having a diameter larger than the core 24 of the take-up spool, whereby initially the web 10 is transported at some distance from the core 24. As the towbar engages a trip a'r'm coupled to the slapper 39, it moves the trip arm 32 toward the left and rotates a gear member 34 clockwise. The gear member 34 drives a second gear member 35 counterclockwise so that a spring 36 will ultimately reach an overcenter posit-ion and rapidly drive the slapper 30 against the web It) and toward the core 24, similar to a snapswitch operation.

The result of the slapper operation is shown more clearly in FIG. 3 wherein the slapper 30 has driven the web against the core 24. The towbar 20 then continues to be driven by its chain-drive 22 to engage a cutter drive mechanism 38 and rotate it on its pivot support 39 so that a cutter blade 40 engages a lead portion 41 of the web 10. At a still later time and further downstream of the core 24, the towbar 20 engages a second trip arm 42 to rotate the gears 34 and 35 in an opposite direction to that described above so that the slapper 30 will reset, as shown in FIG. 2, and the spring 36 is again tensioned to maintain the slapper 30 in the inactive position. In winding Webs wherein the pressure of the slapper 30 may be maintained againstthe web 10 without damage thereto, the trip arm 42 may be omitted, whereupon the increase in size of the reel 16 will ultimately force the slapper 36 to an over-center position to reset it.

Referring now to FIG. 4, the towbar 20 is engaging the lower portion of the cutter drive mechanism 38 to rotate the cutter mechanism about the pivot support 39 so that the cutter blade 46 engages the web portion 41. This engagement is assured by the fact that the web portion 41 is being pulled taut between the spool core 24 and the towbar 20. Thus, the location of the web portion 41 relative to the towbar 20 and the cutter blade is precisely predictable by proper selection of the timing relationship between the operation of the slapper 30, the tangential velocity of the spool core 24, and the movement of the cutter blade 40. Because of static electricity problems in connection with the rapidly moving towbar 20, the trip arm 32, the cutter drive mechanism 38, the cutter blade 40, the web 10, etc., we have provided a grounded shield 43 to protect the unprocessed web from fogging.

It should be noted in FIGS. 2 and 3 that the web 10 in the region of the core 24 is provided with a substantial amount of slack because of the fact that initially it traverses this portion of the equipment at a radius equal to that of the sprocket wheel 25 rather than the radius of the spool core 24. Since the spool core 24 is smaller, slack is provided so that the towbar 20 may move from the position shown in FIG. 3 to that shown in FIG. 4 without ripping the web 10 loose from the core 24. Once the towbar 20 has traversed the region of the cutter drive mechanism 38, the balancing thereof is such that the cutter drive mechanism 38 returns to the stand-by position illustrated in FIGS. 2 and 3.

After separating of the web 10 from the towbar 20, the flap portion of the web is wound on the spool core 24 along with the processed portion of the web 10. Also, the towbar 20 engages an automatic turn-01f switch operator 44 (FIGS. 1 and 2) near the end of its travel path to stop it in the stand-by position as shown in FIG. 1. The rotational velocity of the core 24 is selected so that the operator 44 opens the switch 29 after the feeler 28 is engaged by the web 10. In the stand-by position the towbar 20 will have removed therefrom the portion of the web 10 thereon and thus will be prepared for a later operation.

It should be noted that if the spool core 24 has a circumference of 6" and the web portion 41 a length of 12", only about two feet of the leader is required when using our invention, while the amount of leader between the spool core 24 and the reel 11 (FIG. 1) is of the order of 100 feet or more. Moreover, a considerable threading labor has been eliminated.

While we have shown and described particular embodiments of the present invention, other modifications may occur to those skilled in this art. For instance, usually the core 24 is driven by a magnetic or another type of slipping clutch so that the speed of the web being processed does not vary because of convolution growth of the web 10 on the reel 16. In such cases, positive drive of the web it) is assured by the synchronous drive of some of the rollers 13. Also, in certain operations, it is feasible to perforate the web It) in the web portion 41 sufficiently to assure breakage thereof without engagement by the cutter blade 40. We intend, therefore, to have the appended claims cover all modifications which fall within the true spirit and scope of our invention.

We claim:

1. An automatic web threader operable to thread a web at operating speeds through a tortuous path defined by a plurality of web transport mechanisms comprising:

a web take-up spool core;

a towbar for grasping a leading end of the web;

a chain-drive secured to said towbar for pulling said towbar and the web attached thereto through the tor- V tuous path and past said spool core;

a web grasping means associated with said spool core;

hook-up means operable by said towbar downstream of said spool core to force the web within the control of said grasping means; and

cutter means downstream of said hook-up means operable by said towbar to sever the web between said towbar and said spool core.

2.- An automatic web threader operable to thread a web at operating speeds through a tortuous path of a processing mechanism defined by a plurality of web transport mechanisms comprising:

a web take-up spool core;

a towbar for grasping a leading end of the web;

a chain-drive secured to said towbar for pulling said towbar and the web attached thereto through the tortuous path and past said spool core;

drive means coupled to said chain-drive;

web drive means coupled to said spool core;

switch means for starting said chain-drive and said spool core;

web grasping means associated with said spool core;

hook-up means operable by said towbar downstream of said spool core to forcethe web within the control of said grasping means; and

means downstream of said hook-up means operable by said towbar to separate the web attached to said spool core from said towbar.

3. An automatic web threader operable to thread a web at operating speeds through a tortuous path of a processing equipment defined by a plurality of web transport mechanisms comprising:

a web take-up spool core;

a towbar for grasping a leading end of the web;

towbar drive means for pulling said towbar and the web attached thereto through the tortuous path and past said spool core;

web drive means coupled to said spool core;

switch means for starting said towbar drive means and said web drive means;

web grasping means associated with said spool core;

hook-up means operable by said towbar downstream of said spool core to force the web within the control of said grasping means;

cutter means downstream of said hook-up means operable by said towbar to sever the web between said towbar and said spool core;

a reset means for said hook-up means operable by said towbar downstream of said cutter means;

means for coupling the web to a portion of said switch means to prevent shut-down of said web drive means; and a means operable by said towbar downstream of said reset means for de-energizing said towbar drive means.

4. In an automatic web threader operable to thread a web to a take-up spool core at operating speeds by means of a towbar selectively drivable through a tortuous path of a processing equipment defined by a plurality of web transport mechanisms, a web hook-up and towbar release arrangement, comprising:

web grasping means associated with the spool core;

a slapper operable by the towbar downstream of the spool core to force the web within the control of said grasping means; and

cutter means downstream of said slapper operable by the towbar to sever the web between the towbar and the spool core.

5. In an automatic web threader operable to thread a web to a take-up spool core at operating speeds by means of a towbar selectively drivable through a tortuous path of a processing equipment defined by a plurality of Web transport mechanisms, 21 web hook-up and towbar release arrangement, comprising:

web grasping means associated with the spool core;

means operable by the towbar downstream of the spool core to force the web within control of said grasping means; and

means operable by the towbar for separating the web between the towbar and the spool core.

6. In an automatic web threader for high speed processing equipment, the threader being operable to thread a web to a take-up spool core at operating speeds of the processing equipment by means of a towbar selectively drivable through a tortuous path defined by a plurality of web transport mechanisms, a web hook-up and towbar release arrangement, comprising:

an activated adhesive on the surface of the spool core;

a slapper operable by the towbar downstream of the spool core to force the web within the control of said adhesive;

cutter means downstream of said slapper operable by the towbar to sever the web between the towbar and the spool core; and

switch means operable when the towbar is downstream of said slapper to prevent repeated driving of the towbar through the tortuous path.

7. In an automatic web threader for high speed processing equipment, the threader being operable to thread a web to a take-up spool core at operating speeds of the processing equipment by means of a towbar selectively drivable through a tortuous path defined by a plurality of web transport mechanisms, a web hook-up and towbar release arrangement, comprising:

drive means for driving the spool core at a speed developing a peripheral velocity no less than the speed of the towbar;

means associated with the towbar for activating said drive means prior to the passage of the towbar through the portion of the tortuous path past the spool core;

an activated adhesive on the surface of the spool core;

a slapper operable by the towbar downstream of the spool core to force the web within the control of said adhesive;

cutter means downstream of said slapper operable by the towbar to sever the web between the towbar and the spool core, the peripheral velocity of the spool core and the activation of said cutter means being arranged to place a lead portion of the web within control of said cutter means during activation; and

switch means operable by the towbar downstream of said slapper to prevent repeated driving of the towbar through the tortuous path.

8. In an automatic web threader for high speed processing equipment, the threader being operable to thread a web to a take-up spool core at operating speeds of the processing equipment by means of a towbar selectively drivable through a tortuous path defined by a plurality of web transport mechanisms, a web hook-up arrangement, comprising:

drive means for driving the spool core at a speed developing a peripheral velocity no less than the speed of the towbar;

means associated with the towbar for activating said drive means prior to the passage of the towbar through the portion of the tortuous path closest to the spool core;

high speed web grasping means on the spool core;

a slapper to force the web Within the control of said grasping means operable by the towbar when downstream of the spool core; and

switch means operable when the towbar is downstream of said slapper to prevent repeated driving of the towbar through the tortuous path.

9. In an automatic web threader for high speed processing equipment, the threader being operable to thread a web to a take-up spool core at operating speeds of the processing equipment by means of a towbar selectively drivable through a tortuous path defined by a plurality of web transport mechanisms, a web hook-up arrangement, comprising:

drive means for driving the spool core at a speed developing a peripheral velocity no less than the speed of the towbar;

means associated with the towbar for activating said drive means prior to the passage of the towbar through the portion of the tortuous path closest to the spool core;

high speed web grasping means on the spool core; and

means operable by the towbar when downstream of the spool core to force the web within the control of said grasping means.

References Cited by the Examiner UNITED STATES PATENTS 2,491,981 12/49 Janapol et al. -90.5 2,503,453 4/50 Pratt et al 242-74 3,089,660 5/63 Bilane 242-56 3,096,701 7/63 Edwards 94 JORDAN FRANKLIN, Primary Examiner. 

1. AN AUTOMATIC WEB THREADER OPERABLE TO THREAD A WEB AT OPERATING SPEEDS THROUGH A TORTUOUS PATH DEFINED BY A PLURALITY OF WEB TRANSPORT MECHANISMS COMPRISING: A WEB TAKE-UP SPOOL CORE; A TOWBAR FOR GRASPING A LEADING END OF THE WEB; A CHAIN-DRIVE SECURED TO SAID TOWBAR FOR PULLING SAID TOWBAR AND THE WEB ATTACHED THERETO THROUGH THE TORTUOUS PATH AND PAST SAID SPOOL CORE; A WEB GRASPING MEANS ASSOCIATED WITH SAID SPOOL CORE; 